Reflex sight adjustments

ABSTRACT

A battery compartment for a reflex sight is accessed via a pivoting lid that can be unlatched, opened, and closed by hand without tools and without removing the sight from its weapon. A button carried by the lid actuates a switch within the sight for changing a setting of the sight. Also disclosed is a reflex sight having mounting structures for accessories, such as an impact guard, a rain hood, or a rear iron sight for example. Positioning mechanisms for an LED or other aiming point display device of an aiming sight are also disclosed.

RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. §119(e)from U.S. Provisional Patent Application Nos. 61/926,818, filed Jan. 13,2014, and 62/037,458, filed Aug. 14, 2014, both of which areincorporated herein by reference.

TECHNICAL FIELD

The field of the present disclosure relates to optical aiming devicesand, in particular, to compact reflex sights for handguns, rifles andthe like.

BACKGROUND

Miniature reflex sights, also commonly known as mini red-dot sights, arenon-magnifying reflector sights that are commonly used with handguns andsmall armaments such as rifles and crossbows. Reflex sights are alsoused for other aiming purposes, for example, as a finder scope for usewith a telescopes. Reflex sights typically include a partiallyreflecting transparent element, such as a lens or flat glass element,that the user looks through to view a target and an illuminated aimingmark or reticle pattern that is superimposed on the field of view. In areflex sight utilizing a reflecting lens element, the aiming mark istypically generated by a small light emitting diode at the focal pointof the lens, the latter of which is selectively reflective to thewavelength of the illumination. In reflex sights including a flat glasselement, the aiming mark is generated by an illumination source directedthrough collimating optics toward the flat glass element.

U.S. Pat. No. 6,327,806 of Paige describes a reflex sight and a methodof manufacturing its lens element. Other similar reflex sights aredescribed in U.S. Pat. No. 8,082,688 of Elpedes et al. and U.S. Pat. No.7,916,290 of Koehler.

The present inventor has recognized a need for an improved reflex sighthaving features especially desirable for tactical users.

SUMMARY

In one embodiment, a reflex sight for a handgun includes a batterycompartment for a button cell that powers the illumination electronicsof the sight. The battery compartment is accessed via a pivoting lidlocated on a top surface of a housing of the sight between a reflectingelement of the sight and an aiming mark illumination source. Thepivoting lid is retained by a spring latch that can be operated by handwithout tools and without removing the reflex sight from the weapon, asis the case with many prior art reflex sights wherein the compartment oraccess door is located on an underside of the sight. When closed, thelid is preferably sealed to the housing by an O-ring that is compressedbetween the lid and the compartment opening when the lid is retained bythe spring latch. The lid is preferably biased upwardly by a spring sothat when the latch is released, the lid is urged open. A magnet may bemounted to the underside of the lid to magnetically lift a button cellbattery from the battery compartment when the lid is opened. The buttoncell is preferably movable within the battery compartment by depressinga selector button carried by the lid to thereby actuate an electricalswitch that controls a setting of the reflex sight. The switch maycomprise a miniature metal dome switch contact that also serves as oneof the battery contacts.

In another embodiment, a reflex sight includes one or more mountingfeatures for accessories, such as an impact guard, a rain hood, or arear iron sight, for example. In some embodiments, threaded holes alongleft and right side walls of a main housing of the sight receive screwsthat attach accessories that may extend over the top of the sight. Forexample, an impact guard may be attached over a lens frame of thehousing in which the optical element is mounted. The impact guard may besized and shaped so that when the impact guard is mounted to thethreaded holes, a gap remains between the underside of the impact guardand an arched or flat top region of the lens frame. This gap providesroom for the impact guard to flex and absorb the energy of an impact,which may prevent damage to the optical element. A T-slot, dovetailslot, rail, or other elongate mounting structure may be provided at arear end of the reflex sight for slidably mounting other accessoriesthereto, such as an auxiliary rear iron sight (open sight). An accessoryrear iron sight may be co-witnessed with the illuminated aiming mark ofthe reflex sight and a front iron sight of the weapon, allowing the userto quickly switch or alternate with speed and confidence between the twosighting systems, and to provide a backup aiming device in the event ofa failure of the reflex sight electronics, for example. The rear ironsight may include a traveler block slidably mounted to the T-slot orrail and vertically adjustable therealong by an adjustment screw. Therear iron sight may be attached to the traveler block by alaterally-extending horizontal adjustment screw for effecting horizontalor “windage” adjustments in the rear iron sight. It is envisioned thatreflex sight may include other accessory mounting features for mountingadditional or different accessories not described herein.

Also disclosed is a positioning mechanism for an aiming point displaydevice of an aiming sight, such as a miniature LED that generates anaiming mark reflected in the optical element of a reflex sight. A baseof the aiming device has an elongate cavity formed therein providing aplatform relative to which the positioning system adjusts the positionof the aiming point display device. The aiming point display device issupported on a carriage that is slidably received in the elongatecavity. The carriage has formed therein an undercut slot extending alonga first axis of motion. An elevation adjustment screw is rotatablysupported on the base and extends into the cavity along a second axis ofmotion perpendicular to the first axis of motion. An elevation block isslidably received in the undercut slot of the carriage and threaded ontothe elevation adjustment screw for movement along the second axis ofmotion. At least one sizer bearing is interposed between the bottom ofthe undercut slot and the elevation block, so that the sizer bearingtakes up slop between the elevation block and the undercut slot whileallowing the carriage to slide along the first axis of motion relativeto the elevation block. The sizer bearing may be a self-lubricatingplain bearing block or pad formed of a resinous material. Thepositioning system also includes a windage adjustment screw rotatablysupported on the base and extending into the cavity along the first axisof motion to adjust the carriage along the first axis of motion. Aspring may be provided to urge the carriage toward the windageadjustment screw. A pusher block may be threaded onto the windageadjustment screw and push against the carriage to drive the carriagealong the first axis of motion in response to rotation of the adjustmentscrew. An optional second sizer bearing may be interposed between thecarriage and a wall of the elongate cavity of the body to take up slopalong a third axis perpendicular to the first and second axes of motion.

Additional aspects and advantages will be apparent from the followingdetailed description of preferred embodiments, which proceeds withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a reflex sight according to the presentdisclosure, mounted to a handgun.

FIGS. 2, 3, 4, 5, 6, 7, and 8 are respective right side isometric, leftside isometric, left side elevation, top, rear elevation, frontelevation and right side elevation views of the reflex sight of FIG. 1.

FIG. 9 is a pictorial view of the reflex sight of FIG. 1 illustrating abattery compartment lid being opened for replacing a button cellbattery.

FIG. 9A is a pictorial view of another embodiment of the reflex sightwith a battery compartment lid and latch having features to indicate astate of the latch.

FIG. 10 is a isometric left side section view of the reflex sight ofFIG. 1 taken along line 10-10 in FIG. 5 with a battery compartment lidillustrated in the open position.

FIG. 11 is a section view of the reflex sight of FIG. 1 taken along line11-11 of FIG. 5 to show detail of a rear iron sight mounting block andhorizontal adjustment screw.

FIG. 12 is a partial side section view of the reflex sight of FIG. 1taken along line 12-12 of FIGS. 5-6 with a housing and batterycompartment lid of the reflex sight omitted to show detail of apositioning mechanism for an illumination module of the reflex sight anda circuit board of the reflex sight.

FIG. 13 is an enlarged rear right side isometric view of the positioningmechanism of FIG. 12.

FIG. 14 is an enlarged section view of the reflex sight of FIG. 1 takenalong line 14-14 of FIG. 5 to show detail of the positioning mechanismof FIG. 13.

FIG. 15 is an enlarged isometric section view of the reflex sight ofFIG. 1 taken along line 14-14 of FIG. 5.

FIG. 16 is a side section elevation of the reflex sight of FIG. 1 takenalong line 16-16 of FIG. 7 to show detail of the positioning mechanism.

FIG. 17 is an enlarged detail side section view of the positioningmechanism illustrated in FIG. 16.

FIG. 18 is an exploded view of the reflex sight of FIG. 1.

FIG. 19 is an enlarged lateral section view (an alternate to FIG. 14)illustrating another embodiment of a positioning mechanism for anillumination module of the reflex sight of FIG. 1.

FIG. 20 is a bottom view of the positioning mechanism of FIG. 19 with abackplate of the reflex sight removed to show detail.

FIG. 21 is an enlarged longitudinal section view showing additionaldetail of the positioning mechanism of FIG. 19.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

This section describes particular embodiments and their detailedconstruction and operation. The embodiments described herein are setforth by way of illustration only and not limitation. Throughout thespecification, reference to “one embodiment,” “an embodiment,” or “someembodiments” are not necessarily all referring to the same embodiment.The described features, structures, characteristics, and methods ofoperation may be practiced in isolation or combined in any suitablemanner, and can be practiced without one or more of the specific detailsor with other methods, components, materials, or the like. In otherinstances, well-known structures, materials, or methods of operation arenot shown or not described in detail to avoid obscuring more pertinentaspects of the embodiments.

FIG. 1 illustrates a reflex sight 20 in accordance with a presentlypreferred embodiment, mounted to a slide 22 of a semi-automatic pistol24. With reference to FIGS. 1-2, reflex sight 20 includes a body 30 thatserves as a housing for electronics and other devices described herein,and as a mounting platform for accessory devices as described below withreference to FIGS. 2, 10-11, and 18. Body 30 includes an upwardlyextending frame 34 forming a loop with a lower base portion 38 of body30. An optical element in the form of a non-magnifying lens 40 ismounted in a generally upright position in a forward portion of frame34, providing a viewing window for a target field of view. Light emittedfrom a miniature light emitting diode (LED) 44 (FIGS. 12, 16) positionedat a focal point rearward of lens 40 and within base portion 38 of body30 is reflected rearward toward the user's eye by a dichroic reflectionlayer or coating of lens 40 as collimated light, so that the userperceives the reflected light as an illuminated aiming mark 46 (FIG. 6)superimposed on the field of view at infinite distance.

With reference to FIG. 2, reflex sight 20 includes optional removableaccessories, including an impact guard 50 that serves as a bumper toprotect lens 40, and a rear iron sight module 60 described in greaterdetail below with reference to FIGS. 10-11. Impact guard 50 includesleft and right upstanding legs 64, 66 that are attached to left andright side walls 72, 74 of body 30 via screws 76 threaded into threadedaccessory mounting holes 78 (FIG. 18) in side walls 72, 74. Impact guard50 also includes a bumper portion 80 extending between upper ends oflegs 64, 66 and over frame 34. Impact guard 50 and especially bumperportion 80 are preferably sized, shaped, and/or configured to leave agap 84, best shown in FIG. 16, between an underside of bumper portion 80and an arched top portion 88 of frame 34. Gap 84 provides room forbumper portion 80 of impact guard 50 to flex and absorb the energy of animpact, which may prevent damage to lens 40 in the event of an impact.Impact guard 50 may be made of any suitable strong and energy absorbingmaterial, such as spring steel or high strength plastic resin. In analternative embodiment (not illustrated), impact guard 50 may be made ofan elastomeric material of relatively high durometer forming an armoredlayer on a portion of body 30, in which case impact guard 50 maydirectly abut top portion 88 of frame 34 so as to leave no gaptherebetween.

Accessory mounting holes 78 may also provide attachment points fordifferent accessory items, such as a rain hood (not illustrated) thatmay be mounted over reflex sight 20 to inhibit rain from contacting lens40 and distorting or shifting the location of the aiming mark 46reflected in lens 40. The rain hood may extend over the top and sides ofsubstantially all of reflex sight 20 and perhaps forward and rearwardthereof. The rain hood may be mounted to reflex sight 20 instead ofimpact guard 50, or may be used in conjunction with impact guard 50 bymounting the rain hood over or under impact guard 50 with each of thescrews 76 retaining both the rain hood and impact guard 50 to body 30.In one embodiment, the rain hood may include transparent front and rearwindows having a hydrophobic or hydrophilic coating that preventsdroplets of water from obscuring the optical transmission therethrough.Other types of accessory items mountable to one or more of the mountingholes 78 may include a laser gunsight, a flashlight, a canting indicatorsuch as a bubble level, a range finder, a camera, and/or a displaydevice for images, video and/or data, and any other appropriately sizeditem that may be desired for use with reflex sight 20 or with thehandgun or other aimed device to which reflex sight 20 is mounted.

Turning now to FIGS. 9 and 10, base portion 38 of body 30 defines abattery compartment 102 that houses a button cell 106 that powerselectronics 110 (illustrated in FIGS. 12 and 16) that drive LED 44.Battery compartment 102 is accessed via a pivoting lid 120 that coversan opening 122 to compartment 102 located on base portion 38 betweenlens 40 and LED 44. Lid 120 pivots about a hinge pin 124 that is fittedinto body 30 along a forward edge of opening 122 and is biased upwardlyby a helical torsion spring 128 that is also carried by hinge pin 124and operably interposed between body 30 and lid 120. Lid 120 is retainedin its closed position illustrated in FIGS. 1-8 by a spring latch 140including a latch button 144 slidably mounted in a slot 148, bestillustrated in FIG. 18, that adjoins opening 122 to battery compartment102. Lid 120 may be recessed below the surface of base portion 38 toprovide a clear optical path for illumination generated by LED 44 toreach lens 40. Slot 148 may have undercut sidewalls or an invertedT-shaped cross section (not illustrated) to slidably retain latch button144 therein for movement in a generally horizontal radial direction fromopening 122. A latch spring 152 (FIG. 18) is seated in a bore 156 in thebase of slot 148 and extends into a pocket (not shown) on an undersideof latch button 144 to urge latch button 144 to the latched positionillustrated in FIGS. 1-8, where an inner lip of latch button 144 extendsover lid 120 to retain lid 120 in its closed position. Latch 140 isoperable to provide access to battery compartment 102 to replace buttoncell 106 without removing reflex sight 20 from weapon 24 or otherwisedisturbing its aim. Latch 140 is released by sliding the latch button144 outwardly in slot 148 in the direction illustrated by arrow 158 inFIG. 9, thereby allowing lid 120 to be urged open by torsion spring 128or another biasing device. A small slot or notch 162 is provided in atop of latch button 144 to assist in grasping latch button 144 with auser's fingernail for toolless opening, or with the rim of a cartridge,a coin, or another tool. When closed, lid 120 is preferably sealed tobody 30 by an O-ring 166 that is compressed between lid 120 and atapered surface 172 (FIG. 10) bordering opening 122. O-ring 166 ispreferably fitted in a channel encircling lid 120 and prevents moistureand debris from entering battery compartment 102 when lid 120 is closed.FIG. 10 includes a cross section of lid 120, and shows a magnet 178 thatmay be mounted to the underside of lid 120 to magnetically lift buttoncell 106 from battery compartment 102 when lid 120 is opened.

With reference to FIG. 10, lid 120 includes a setting switch 125including a selector button 121 formed of an elastomeric or flexibleplastic material that is manually depressible to actuate switch 125 andthereby control a setting of sight 20. Selector button 121 may allow agloved user to control of a setting of the sight 20, such as anillumination mode, illumination brightness, reticle pattern, or otherattribute of illuminated aiming mark 46 (FIG. 6). Button cell 106 ismovable within battery compartment 102 in response to manuallydepressing selector button 121, and a central region of selector button121 is depressible to push button cell 106 downwardly against aminiature metal dome switch contact 126 that forms the moving contact ina miniature snap-action switch or microswitch. Depressing selectorbutton 121, button cell 106 and dome switch contact 126 causes domeswitch contact 126 to flex so that a central portion thereof comes intoelectrical contact with a contact pad 127 on an upper side of a circuitboard carrying electronics 110, thereby closing the setting switch 125.Dome switch contact 126 also preferably serves as a battery contact.When the downward force on selector button 121 is released, the domeswitch contact 126 provides a spring return force that automaticallyreturns button cell 106 and selector button 121 to their initialposition.

Selector switch 125 provides signal input to electronics 110 and mayallow a user to cycle through various illumination settings of sight 20.For example, in one embodiment, selector button 121 is depressed totoggle between an automatic mode and one or more manual modes for anillumination setting of aiming mark 46. In an automatic mode, a lightsensor (not shown) of sight 20 may measure ambient light and abrightness control circuit may automatically determine and set anappropriate illumination intensity of aiming mark 46 based on themeasured ambient light. In a manual mode, the user may cycle throughvarious illumination settings by manually depressing selector button 121multiple times until a desired light intensity level is obtained. Insome embodiments, depressing selector button 121 may cycle throughseveral settings in sequence, including: ON (Auto), high intensity,medium intensity, low intensity, and OFF.

Turning briefly to FIG. 21, another embodiment of selector button 521includes a gasket portion 528 that extends underneath lid 520 andencircles lid 520 to provide a hermetic seal between lid 520 and body530 and to prevent moisture and debris from entering the batterycompartment when lid 520 is closed. Thus, selector button 521 of FIG. 22serves the function of both the button 121 and O-ring 166 of theembodiment of FIGS. 9 and 10.

FIG. 9A illustrates another embodiment of a spring latch 140 a forbattery compartment lid 120 a, shown in its unlatched but closed state.In the embodiment of FIG. 9A, spring latch 140 a is manually operable tounlatch lid 120 a and provide access to the battery compartment in asimilar fashion as described with reference to FIG. 9. A latch slide 144a rides in a through slot 148 a such that an end 141 a of latch slide144 a is visible on an exterior surface 31 a of body 30 a. In sucharrangement, the position of latch slide 144 a relative to exteriorsurface 31 a provides a quick-reference tactile and visual indication tothe user whether latch 140 a is in a latched or unlatched position. Whenlatch 140 a is in the latched position (not shown), an outer end 141 aof latch slide 144 a is aligned with and is substantially flush withexterior surface 31 a of body 30 a, and an inner lip of latch slide 144a extends over lid 120 a to retain lid 120 a in its closed position.When latch 140 a is in the unlatched position, as shown in FIG. 9A,outer end 141 a protrudes outwardly beyond exterior surface 31 a toprovide a tactile indicator to the user that latch 140 a is unlatched.In some embodiments, lid 120 a may further include a contrastingindicator mark 123 a, such as a stripe or other highly visible mark,that is revealed when latch slide 144 a is unlatched and pulled awayfrom lid 120 a. When latch 140 a is in the latched position, the innerlip of latch slide 144 a covers indicator mark 123 a.

With reference to FIGS. 2 and 10, provided at a rear end 186 of reflexsight 20 is an elongate guideway 190, preferably in the form of undercutslot, such as a T-slot or dovetail slot for mounting accessoriesthereto. In other embodiments (not illustrated), guideway 190 may takethe form of a rail, such as a T-rail, instead of an undercut slot. Instill other embodiments, a different kind of mounting attachment point,such as a socket, pocket, hole or pin may be provided at the rear ofreflex sight 20. An auxiliary rear iron sight assembly 60 is mounted inguideway 190 as further described below. Rear iron sight assembly 60includes an iron sight block 194 having an open sight slot 198 that maybe co-witnessed with illuminated aiming mark 46 (FIG. 6) of reflex sight20 and a front iron sight 202 (FIG. 1) of weapon 24. Rear iron sightassembly 60 may enable the user to quickly switch or alternate withspeed and confidence between the two sighting systems, and to provide abackup aiming device in the event of a failure of the electronics 110 ofreflex sight 20, for example. Rear iron sight assembly 60 includes atraveler block 210 having a T-shaped rail 212 slidably mounted toguideway 190 and vertically adjustable therealong by an iron sightelevation adjustment screw 216 comprising a grub screw that bearsagainst a backplate 230 (FIG. 10) of reflex sight 20 (and ultimatelyagainst slide 22 of weapon 24) to jack the traveler block 210 upwardly.A pair of set screws 234 are threaded into left and right side walls 72,74 of base 30 and extend into guideway 190 to bear against travelerblock 210 and secure the vertical position of traveler block 210 inguideway 190 once set. To change the vertical position of traveler block210, set screws 234 must first be loosened.

In other embodiments (not illustrated), reflex sight 20 may includemounting features for fitting other commercially available iron sightsor accessories. For example, rear end 186 of reflex sight 20 may includea lateral dovetail slot (not shown), that can be used to mount anddismount sight accessories, such as a rear iron sight accessory. In suchan embodiment, the rear iron sight accessory may slide into the dovetailslot and be secured in a similar manner as described previously relativeto the rear iron sight assembly 60. The rear iron sight accessory may beeasily removed and replaced to allow the user to switch between variousrear iron sight accessories or other accessories.

With reference to FIGS. 10 and 18, a rubber gasket 238 is providedbetween backplate 230 and body 30 of reflex sight 20 and compressedtherebetween by four screws 240 connecting backplate 230 to body 30 frombelow. Rubber gasket 238 is designed to prevent moisture from enteringbody 30. In another embodiment, not illustrated, a double sided filmtape may be utilized to bond backplate 230 to body 30, which providessealing and adhesion that allows screws 240 to be eliminated, therebyreducing cost. Improved waterproof performance was tested to a depth of66 feet for two hours through the use of 3M VHB™ brand double-sided filmtape in place of rubber gasket 238 and screws 240.

With reference to FIG. 11 showing a cross section of rear iron sightassembly 60 taken along line 11-11 of FIG. 5, rear iron sight block 194is attached to traveler block 210 by a laterally-extending iron sightwindage adjustment screw 224 for effecting horizontal or “windage”adjustments to the rear iron sight block 194. Windage adjustment screw224 is supported on left and right stanchions 242, 244, with a head 248of adjustment screw 224 seated in a counterbore 252 in right stanchion244. A retaining clip, such as an E-clip 258, is attached to windageadjustment screw 224 in a groove between head 248 and a shoulder 262 ofscrew 224 to rotatably secure screw 224 to right stanchion 244. AnO-ring 266 or other resilient member is positioned under head 248 andcompressed between head 248 and the bottom of counterbore 252 to take upslop. With reference to FIG. 12 showing a partial cross section takenalong line 12-12 of FIG. 5, head 248 of iron sight windage adjustmentscrew 224 includes detent grooves. A detent pin 270 is slidably receivedin a bore and urged toward head 248 by a click spring 274 captured inthe bore, to thereby engage the detents on head 248 and facilitateincremental horizontal adjustment of iron sight block 194. As shown inFIG. 10, a resilient spacer bearing 280 is interposed between iron sightblock 194 and traveler block 210 forwardly of windage adjustment screw224 to prevent traveler iron sight block 194 from rocking about screw224.

In some embodiments, the slide 22 of pistol 24 may include a dovetailslot sized for receiving various standard rear iron sights, such as acut sight. With the dovetail slot in slide 22, a user may easily andquickly replace an iron sight assembly with a reflex sight assembly bysimply sliding out the rear iron sight from the dovetail slot andslotting in the reflex sight. The reflex sight may, thus, include adovetail wedge extending from a bottom surface of the sight to beslidably received in the dovetail slot for mounting the sight directlyto the dovetail slot without other anchors or gunsmithing.

Positioning Mechanism for Aiming Mark Display Device (LED)

FIG. 12 is a partial side section view of reflex sight 20 taken alongline 12-12 of FIGS. 5-6 with body 30 and battery compartment lid 120omitted to show detail of a positioning mechanism 300 for LED 44 thatgenerates an aiming mark reflected in the optical element of a reflexsight. LED 44 is coupled to electronics 110 (FIGS. 10 and 16) by a flexcircuit 306. A transparent window 312 is mounted to body (not shown) infront of LED 44 to allow illumination from LED to pass therethrough andbe reflected in lens 40 for generating the aiming mark 46 describedabove.

FIG. 13 is an enlarged right rear side isometric view of positioningsystem 300 with other parts of reflex sight 20 omitted. FIGS. 14-17provide sectional views of reflex sight 20 and positioning system 300along section lines described above in the Brief Description of theDrawings. With reference to FIGS. 13-17, base 30 has an elongate cavity320 (FIG. 14) formed therein providing a platform relative to whichpositioning system 300 adjusts the position of the LED 44. LED 44 issupported on a carriage 330 of positioning system 300 that is slidablyreceived in the cavity 320. As best illustrated in FIGS. 13 and 17,carriage 330 has formed therein an undercut slot 336 extending along afirst axis of motion 340 (FIG. 13). Undercut slot 336 is preferably aT-slot, but may be made in other shapes, such as dovetailed for example.Slot 336 opens at a right-hand end of carriage 330 proximate a windageadjustment screw 350 and pusher block 360 of positioning system 300,described below.

An elevation adjustment screw 370 is rotatably supported on the base andextends into cavity 320 along a generally vertical second axis of motion380 perpendicular to first axis 340. Windage and elevation adjustmentscrews 350, 370 extend through unthreaded countersunk holes 392, 394,respectively, in body 30, so that tapered heads of the adjustment screws350, 370 are seated in the countersinks, and retained therein by E-clips398 clipped to a shoulder groove of screws 350, 370 and abutting theinternal walls of cavity 320. O-rings 402 seal adjustment screws 350,370 to housing and urge them outwardly to take up slop. Click pins 410are slidably received In angled bores 412 and urged by click springs 414against detents in the tapered head surfaces of adjustment screws 350,370 to provide incremental tactile feedback and to prevent inadvertentmovement of screws 350, 370.

An elevation block 430 of positioning mechanism 300 is slidably receivedin undercut slot 336 of carriage 330 and threaded onto elevationadjustment screw 370 for movement of elevation block 430 and carriage330 along second axis 380. Elevation block 430 may be shaped as a T-nut.In other embodiments (not illustrated), the T-slot arrangement may bereversed so that undercut slot 336 is formed in elevation block 430 andcarriage 330 is seated in and linearly slidable along the undercut slotalong first axis 340. A pair of elevation sizer bearings 440 areattached to a bottom surface of elevation block 430 and spaced apart sothat they are interposed between elevation block 430 and a bottom of theundercut slot 336. Sizer bearings 440 take up slop between elevationblock 430 and the undercut slot 336 while allowing carriage 330 to slidealong first axis 340 relative to elevation block 430. Sizer bearings 440may be self-lubricating plain bearing blocks or pads formed of aresilient resinous material, such as PTFE (polytetrafluoroethylene), forexample. The threaded connection between elevation adjustment screw 370and the threaded hole in elevation block 430 may be lined with a similarresin material to reduce or eliminate slop or backlash in the threads.

Windage adjustment screw 350 extends into cavity 320 along first axis340 to adjust the position of carriage 330 along first axis 340. Apusher block 360 is threaded onto windage adjustment screw 350 andpushes against carriage 330 to drive carriage 330 along first axis 340in response to rotation of windage adjustment screw 350. As bestillustrated in FIG. 13, pusher block 360 is T-shaped to provide a guiderail along which vertical fingers 450 of carriage 330 are guided duringvertical travel of carriage 330. In alternative embodiments (not shown),pusher block 360 may take a different shape providing a guide track forcarriage 330. A spring 460 is interposed between a wall of cavity 320and carriage 330 opposite pusher block 360 to urge carriage 330 towardpusher block 360 and windage adjustment screw 350. Horizontal sizerbearings 470 are interposed between carriage 330 and a rear wall of thecavity 320 to take up slop or tolerance deviations along a third axis480 perpendicular to the first and second axes of motion 340, 380. In analternative embodiment (not illustrated), horizontal sizer bearings 470may be interposed between a front wall of carriage 330 and a forwardwall of cavity 320. Backlash in the threads of windage adjustment screw350 may be reduced or eliminated in the same manner as elevationadjustment screw 370, described above.

FIGS. 19-21 collectively illustrate another example embodiment of apositioning mechanism 500. The positioning mechanism 500 may includemany of the same components as the positioning mechanism 300 thatoperate in the same or substantially similar manner as described withrespect to the positioning mechanism 300. Accordingly, the followingdiscussion may generally reference these components to provide a frameof reference with regard to the embodiment of FIGS. 20-21, but will notprovide further detail to avoid repetition. With reference to FIGS.19-21, windage and elevation adjustment screws 502, 504 extend throughunthreaded countersunk holes 506, 508, and are secured against theinternal walls of cavity 510 in a similar fashion as describedpreviously with respect to positioning system 300. The elevationadjustment screw 502 is rotatably supported on the base and extends intocavity 510 along a generally vertical second axis of motion 380 (seeFIG. 13) perpendicular to first axis 340 (see FIG. 13). An elevationblock 512 is threaded onto elevation adjustment screw 502 for movementof the elevation block 512 along the second axis 380. With particularreference to FIG. 22, the elevation block 512 is positioned underneaththe carriage 330, which supports the LED 44. In a similar fashion asdescribed previously, movement of the elevation block 512 urges movementof the carriage 330 and adjustments of the LED 44. One or more springs514 provide a downward force on top of the carriage 330 toward theelevation block 512 to stabilize the carriage 330, and to eliminate slopand backlash in the positioning mechanism 500, including in the threadsof elevation adjustment screw 502.

Skilled persons will appreciate that positioning mechanism 300 may beused with other aiming devices other than reflex sights, to supportilluminated aiming point display devices different from LED 44 toachieve precise positioning and adjustment of such display devices.

It will be obvious to those having skill in the art that many changesmay be made to the details of the above-described embodiments withoutdeparting from the underlying principles of the invention. The scope ofthe present invention should, therefore, be determined only by thefollowing claims.

The invention claimed is:
 1. An aiming device, comprising: a base havingan elongate cavity formed therein; a carriage slidably received in theelongate cavity, the carriage defining an undercut slot extending alonga first axis of motion; an aiming point display device supported on thecarriage; an elevation adjustment screw rotatably supported on the baseand extending into the cavity along a second axis of motionperpendicular to the first axis of motion; an elevation block slidablyreceived in the undercut slot of the carriage and threaded onto theelevation adjustment screw for movement along the second axis of motion;a sizer bearing interposed between a bottom of the undercut slot and theelevation block, the sizer bearing taking up slop between the elevationblock and the undercut slot while allowing the carriage to slide alongthe first axis of motion relative to the elevation block; and a windageadjustment screw rotatably supported on the base orthogonally to theelevation adjustment screw and extending into the cavity along the firstaxis of motion to adjust the carriage along the first axis of motion. 2.The aiming device of claim 1, further comprising at least one secondsizer bearing interposed between the carriage and a wall of the elongatecavity to take up slop along a third axis perpendicular to the first andsecond axes of motion.
 3. The aiming device of claim 1, wherein thesizer bearing is a self-lubricating plain bearing element made of aplastic material.
 4. The aiming device of claim 1, further comprising apusher block threaded onto the windage adjustment screw and pushingagainst the carriage to drive the carriage along the first axis ofmotion in response to rotation of the windage adjustment screw.
 5. Theaiming device of claim 1, wherein the aiming device is a reflex sightand the aiming point display device includes a miniature light emittingdiode.
 6. The aiming device of claim 3, wherein the plastic material ispolytetrafluoroethylene.
 7. The aiming device of claim 1, wherein theelevation adjustment screw includes detents in a tapered head surface,and the base includes an angled bore, the aiming device furtherincluding: a click spring received in the angled bore; and a click pinslidably received in the angled bore and directly abutting the taperedhead of the elevation adjustment screw and the click spring.
 8. Theaiming device of claim 1, wherein the windage adjustment screw includesdetents in a tapered head surface, and the base includes an angled bore,the aiming device further including: a click spring received in theangled bore; and a click pin slidably received in the angled bore anddirectly abutting the tapered head of the windage adjustment screw andthe click spring.
 9. The aiming device of claim 1, wherein the sizerbearing includes a spaced-apart pair of bearing elements.
 10. The aimingdevice of claim 2, wherein each of the sizer bearing and the secondsizer bearing includes a spaced-apart pair of bearing elements.